There really is no set return level regardless of what a particular system or technique claims. Returns are completely dependant on the individual trader; his/her style of trading; and their tolerance for loss.
If you are comfortable risking 10% of capital,then your positions will most likely turn over a higher percentage based on probability. If you are confident in your approach and in the position you are taking on the chart, then you are willing to risk more - hence, gain more.
There are times when I will open up on the euro and it will not go the way I expected - rather than take the loss, often I will hold the position into the night because I am comfortable with my margin usage and expect the european opening to "take care of me" - and it often does. IF the news out of europe prior to the opening of their market is not so favorable - then I would decide to close and take the loss.